Table of documentation contents

Go

A Go client library for Weaviate.

Installation and setup

To get the latest stable version of the Go client library, run the following:

go get github.com/semi-technologies/weaviate-go-client/v2

This API client is compatible with Go 1.13.

You can use the client in your Go scripts as follows:

package main

import (
	"context"
	"fmt"
	"github.com/semi-technologies/weaviate-go-client/v2/weaviate"
)

func GetSchema() {
    cfg := weaviate.Config{
        Host:   "localhost:8080",
		Scheme: "http",
    }
    client := weaviate.New(cfg)

    schema, err := client.Schema().Getter().Do(context.Background())
    if err != nil {
        panic(err)
    }
    fmt.Printf("%v", schema)
}

Authentication

Authentication can be added to the configuration of the client as follows:

token := &oauth2.Token{
    AccessToken:  "<token>",
    TokenType:   "Bearer",
}
cfg := weaviate.Config{
    Host:   "weaviate.example.com",
    Scheme: "https",
    ConnectionClient: oauth2.NewClient(context.Background(), oauth2.StaticTokenSource(token)),
}
client := weaviate.New(cfg)

References

All RESTful endpoints and GraphQL functions references covered by the Go client, and explained on those reference pages in the code blocks.

Design

Builder pattern

The Go client functions are designed with a ‘Builder pattern’. A pattern is used to build complex query objects. This means that a function (for example to retrieve data from Weaviate with a request similar to a RESTful GET request, or a more complex GraphQL query) is built with single objects to reduce complexity. Some builder objects are optional, others are required to perform specific functions. All is documented on the RESTful API reference pages and the GraphQL reference pages.

The code snippet above shows a simple query similar to RESTful GET /v1/schema. The client is initiated with requiring the package and connecting to the running instance. Then, a query is constructed with getting the .Schema with .Getter(). The query will be sent with the .Go() function, this object is thus required for every function you want to build and execute.

Change logs

v2.2.0

  • The new version is compatible with Weaviate v1.4.0 (supports the new img2vec-neural module).

v2.1.x

  • Added QnA-transformers module support.

v2.0.x

This change contains breaking changes over previous version as it is aligned with the new API of Weaviate v1. Use the client version v2.0.0 and up for Weaviate instances running v1.0.0 and up. Use client version v1.1.x for Weaviate version 0.23.y. Changes (and migration guide):

  • .WithKind() removed

    Due to the removal of semantic Kinds (“things/actions”) in Weaviate, the .WithKind() method is removed on all builders

  • .WithSchema() -> .WithProperties()

    Due to the renaming of Object.Schema to Object.Properties in Weaviate, all .WithSchema(propertySchema) methods were renamed to .WithProperties(propertySchema)

  • .WithAdditionalInterpretation() => .WithAdditional("interpretation") on ObjectsGetter

    This change reflects two changes in Weaviate: First up, “Underscore Properties” are now called “Additional Properties”, furthermore the presence of such properties may depend on modules and is thus now dynamic. As such, the desired additional property is now passed in as a string.

    Note: There is one exception: .WithVector() can still be used, as the field vector has been “upgraded” from an underscore/additional property to a regular property

  • .WithExplore() -> .WithNearText()

    Following the renaming of explore to nearText in Weaviate the builder method was renamed accordingly. Additionally, the new method .WithNearVector("{vector: [...]}") was introduced to allow for nearVector searches.

  • .WithK(3) -> .WithSettings(&classification.ParamsKNN{K: &k}) in classification builder

    To reflect the API changes in the classification builder the kNN-specific method .WithK(), was replaced with a more generic .WithSettings(interface{}) which takes any classification type-specific settings, such as &classification.ParamsKNN{K: &k} for kNN or &classification.ParamsContextual{TfidfCutoffPercentile: &value} for text2vec-contextual.

More Resources

If you can’t find the answer to your question here, please look at the:

  1. Frequently Asked Questions. Or,
  2. Knowledge base of old issues. Or,
  3. For questions: Stackoverflow. Or,
  4. For issues: Github. Or,
  5. Ask your question in the Slack channel: Slack.
Tags
  • go
  • client library